Atrial fibrillation (AF) is the most common sustained disturbance of cardiac rhythm, affecting an estimated 2.3 million people in North America and 4.5 million people in the European Union. Although af is associated with significant morbidity, mortality, and increased health care costs, more-precise and less-invasive surgical ablation procedures have been developed. Specific cardiac sites emitting the aberrant, premature electrical signals that induce AF are ablated, which results in excellent cure rates and allows normal sinus rhythm to resume. These procedures can be performed with or without the use of cardiopulmonary bypass, through either traditional sternotomy or minimally invasive thoracotomy incisions.